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By Art Wright, Steinar L. Ellefmo, Kurt Aasly, Mike Williamson, Fredrik Søreide, Martin Ludvigsen, Michael Zylstra

Exploring for minerals on the seabed is challenging and expensive – and the ability to collect representative sub surface samples is essential. The research project MarMine led by NTNU has together with Seattle based Williamson and Associates developed and tested an ROV-based drill rig for mineral (seafloor massive sulfides and crusts) and rock sampling. The ROCS system is a single stroke drill and is simple, robust and possible to use from various larger ROVs. For the vehicle to provide a stable platform, the vertical bollard pull of the ROV and the vehicle mass are important variables. The developed drill uses a thin wall drill bit and barrel and operates at high RPM to reduce the required down weight and drilling moments. The system also contains an emergency release to be used if the core barrel is stuck. The drill is hydraulically powered with cylinders operating the tower and a rotation unit. It can rapidly be modified to provide samples from softer samples like unconsolidated material. At the Arctic Mid Ocean Ridge, a work class ROV was deployed with the drill mounted for testing at 2700 m depth in basalt rock. The recovery from the system was above 80%. Such core samples can be used for chemical analyses of metal and mineral grades, mineralogy and rock mechanical testing. The system provides a probing tool for marine mineral exploration, with low cost, low operational complexity and low risk. Proper resource estimation requires drilling deeper into the deposit, but the short core samples provided by the ROCS provide valuable a priori information planning for more extensive drilling campaigns.

Jan 1, 2017

By V. M. Hamza

Analysis of ground and airborne radiometric measurements in the Saquarema region (Rio de Janeiro) provides new insights into the breakdown and transport of mineral aggregates containing monazites, under sub-tropical weathering conditions. The breakdown process, accompanied by loss of low-density clay fractions in weathered materials is considered responsible for the observed patterns in relative enrichment of thorium and uranium along the migration paths of radionuclides. The characteristic features of these patterns provide clues as to the time and distance scales associated with processes of weathering and erosion. It is also possible to determine approximate locations of concentrations of accessory minerals. In this context, we advance the hypothesis that large under-water monazite deposits may be present along the offshore sand banks, in the coastal region of the state of Rio de Janeiro.

Sep 14, 2011

By S. Rajendran

The western continental margin comprises of the southwest coast (Cape Comorin-Mangalore), centralwest coast or Konkan coast (Mangalore-Bombay), northwest coast (Bombay-Gulf of Kutch) and the Laccadives area. Placer deposits of heavy minerals occur in discontinuous patches on the beaches along many parts of the west coast. The richest offshore placer deposits occur along the 25 km stretch of the southwest coast from Neendakara to Kayamkulam. The National Institute of Oceanography (NIO) surveys show that the sediments off the Konkan coast consist largely of silty sand, sandy silt and clay and the concentration of ilmenite is higher than the onshore. The heavy mineral concentration ranges up to 90% and has mainly ilmenite and magnetite with minor quantities of apatite, rutile, zircon, kyanite etc. The heavy mineral sands extend below the clays to water depth down to 20 m. The heavy minerals sands vary in thickness from 2-10 m. Offshore placers can be mined by using wire-line, bucket ladder and hydraulic dredges. Wire-line, bucket ladder and hydraulic dredges. Wire-line dredges may employ drag buckets or clamshell and hydraulic dredges suction or airlift principles. The dredges can be located on flat bottom or catamaran barges. Dredging of very near shore placers may be achieved by operating from land. The bucket ladder type of dredger has greater digging ability and hence can be deployed for mining placers which are partly consolidated or cemented or where the most valuable part of the deposit lies at the contact between the alluvium and the bedrock. This type operates very economically up to 45 m depth and needs minimum power requirement per unit dredged. Suction type hydraulic dredges can be operated very effectively up to 60 m water depths. This system is quite ideal for the inner shelf. The maximum practical economic working water depths for wire-line dredges are about 150 m. With the drag bucket modified into large net buckets, the method can be utilized to greater depths. They can be used in areas of high water currents and swells. The type of bucket can be changed readily with change in the nature of alluvium or substratum. The hydraulic suction dredge is the most suitable system for mining unconsolidated sediments. When the sediments are semi-unconsolidated, a cutter head can be mounted on the lower end of the suction pipe to agitate the seabed.

Jan 1, 1996

By Steinar L. Ellefmo, Thomas Kuhn

The deep-sea ocean floor offers a great potential for mineral resources. The evaluation of these resources is both time consuming and costly and require as any resource evaluation data; geodata. The collection of hard data, physical samples, is of course preferred because the associated uncertainty is low. However, the collection of soft data or image derived data can offer a valuable supplement. In this paper image derived nodule uncertain abundance data from an area in the Pacific is utilized. Implementing these uncertain data improves the estimation when the quality of the estimation is measured using the classification indicators like the kriging standard deviation, the relative prediction error, the slope of regression and the weight of the mean. It is concluded that uncertain data is better than no data. INTRODUCTION The deep-sea offers vast mineral resources (Cathles (2011), Hannington et al. (2011), Hannington (2013), Singer (2014)). A mineral resource can according to increasing geological confidence be classified as an inferred, an indicated or a measured resource. The classification is performed by a competent- or qualified person and is dependent on the amount, quality and characteristic of available geodata. The competent person must have at least five years of experience relevant to both the style of mineralisation, the type of deposit and the performed task. Typical examples of a “task” is for example resource estimation and classification or planning- and execution of exploration activities and presentations of the results. The competent person must also be a member or a fellow of a professional organisation and thereby be bound by reporting code (-s) that defines minimum standards, recommendations and guidelines for public reporting.

Jan 1, 2018

By André. C. Louw

Diamond production from the reworked beach and river channel gravels along the west coasts of South Africa and Namibia is well known throughout the world, not only for the exceptional quality of the diamonds, but also for the sheer scope of the operations. To date an estimated 140 million carats have been produced from the resource worth some US$40 billion in today's money terms. It is therefore not surprising that it didn't take long before the attention turned towards the possible extension of this valuable diamond resource on similar submerged beaches in the adjacent territorial waters of South Africa and Namibia. This has proved to be a very successful move as the marine production in Namibia today constitutes 48% of that country's total diamond production. Although small scale recovery of diamonds from the sea commenced in the 1950's, the first large scale production came from the operations of the Texan entrepreneur, Sam Collins, in the 1960's. The De Beers Group, which took over Sam Collin's operations in 1969 had all the concession areas, as well as the financial and human resources to tackle the new mining frontier in the correct way by years of data gathering (ie diamond reserves and seafloor terrain studies) before commencing with large scale mining operations in the 1980's. Those who are familiar with the beach mining operations along the South African and Namibian west coasts will have appreciation for the daunting task of surgically removing the payable portion of diamond deposits from the non-payable material on the one hand, and the complex uneven fractured and gullied bed-rock floor of the deposits on the other hand. Not to mention the additional complexities of large boulders and hard calcretised diamond gravel layers (conglomerate) which are sometimes associated with the deposits. It was a natural development that the sea diamond mining operations were approached with the known information of the land operations, attempting to duplicate land mining operations in the sea, but taking cognisance of the variations of the terrain in the different areas. For instance, we encounter the following variations, and combinations, off the Namibian Coast. ? Close inshore - holocene sand cover often masks large areas of potentially diamondiferous gravels. ? In midwater areas (40m - 100m)

Jan 1, 1998

By Charles W. Finkl

Coastal and marine aggregate (sand and gravel) mining on US continental shelves is a major activity that supplies industrial and commercial demands for these raw materials. Because Pacific, Atlantic, and Gulf coasts contain significant shoreline segments that are in a critical state of erosion, sand-gravel and mixed sediment (sands with a high percentage of silt-plus-clay) deposits are mined in efforts to mitigate land loss. Sandy shores, and to a limited extent gravel coasts, erode by shoreline retreat due to relative sea-level rise and sediment starvation in littoral drift patterns. Mostly gravel shores occur in high latitudes and shorelines often advance seaward due to isostatic rebound following the LGM (Last Glacial Maximum 18,000 YBP). Sandy and fine-grained shores occurring in middle and low latitudes of the conterminous United States are problem coasts that require beach renourishment and reconstruction of barrier islands. Muddy coasts of the Mississippi Delta region are especially problematic because some islands are literally disappearing in response to subsidence. Replacement of sediments lost to the littoral drift system or returned to sedimentary sinks by drowning is thus a critical endeavor that involves annually dredging hundreds of millions of cubic meters of sediments from the continental shelf area. The types of shelf sediments that are amenable to marine mining techniques, their occurrence, and means of detection are highlighted in this paper. Minable Sediments on the Continental Shelf Wide varieties of sedimentary bodies that occur on the continental shelf are amenable to mining for beach renourishment and barrier island (beach-dune-marsh system) reconstruction. Relict terrestrial deposits make up a small but important proportion of shelf sediments that were deposited on coastal plains, now drowned by the post-glacial sea-level rise to form continental shelves. Examples of these deposits include drowned moraines, outwash plains, eskers, and kettles along the northern Atlantic coast in addition to siliciclastics along middle latitude Pacific, Atlantic, and Gulf coasts. Special cases include carbonate sequences along tropical costs of Florida and the muddy coasts of deltas, mostly in Louisiana. Specific types of minable deposits thus include shoreface attached sand sheets, dunes, and ridges in addition to offshore inter-reefal sands (between coral reefs in the Florida Reef Tract), bank deposits, and sand waves (ridges) that extend into US territorial waters. Nearshore siliciclastics include ebb-tidal deltas and bars. Drowned river valleys occur along all three US coasts and can be exploited for their fluvial sands if the covering mud sheets are thin.

Jan 1, 2005

By Karsten Hagenah, Tor Jensen, Jens Laugesen, Øyvind Fjukmoen, Lucy Brooks

This paper describes operational environmental threshold levels for exploitation of mineral resources in the deep sea. Such criteria are needed to be able to monitor and control deep sea mining with respect to the stringent environmental requirements that are needed. It is recommended to use existing environmental threshold levels for comparable activities where such are existing. Fields of application are mainly but not exclusively seabed mining operation activities under the governance of the International Seabed Authority (ISA). The threshold levels and limits mentioned in this paper are proposed recommendations based on other activities than seabed mining but are a proven and accepted approach in other maritime industry activities. An example of such other activities with proven and accepted environmental threshold levels are Oil & Gas exploitation activities in the sea. Background The first exploitation of mineral resources is coming closer. At the moment regulations for exploitation for mineral resources in the Area are being developed by the International Seabed Authority (ISA). The ISA regulations will contain the framework related to environmental monitoring of exploitation. However, the regulations will not contain operational environmental threshold levels for the Contractor.

Jan 1, 2018

By Allan Spencer

In March 2007, Nautilus Minerals Inc. announced that they had commenced their 2007 exploration and development program with the mobilization of the Research Vessel Wave Mercury and the Survey Vessel Aquila onsite Papua New Guinea.

By Robert G. Ditchburn, Albert Zondervan, Akira Usui, Hiroshi Shibasaki, Hajime Hishida, Ian J. Graham

Earlier reconnaissance geological survey and recent mineral exploration by the Geological Survey of Japan (now part of AIST), Metal Mining Agency of Japan (now part of JOGMEC) have revealed that hydrogenetic ferromanganese crusts are widespread over rock outcrops of the floor of the NW Pacific Ocean, south and east of the Japanese Islands, despite vigorous tectonic activity, such as subduction and backarc spreading. Deposition of ferromanganese oxides has occurred since at least the mid-Paleogene over the Philippine Sea Plate region and nearby.

By Christian Müller, Hermann-Rudolf Kudrass, Christian Reichert

Recent studies estimate the depletion mid-point (dmp) for conventional natural gas to be reached around year 2022, and for conventional oil to be reached around year 2017. These numbers are based on simplified assumptions of unchanged demand and do not include increasing reserves from discovery of new fields and also do not include a shifting of resources to reserves e.g. due to an increasing oil price (Gerling et al., 2005). Anyhow, these prospects require conventional hydrocarbons to be substituted in the near future.

Aug 24, 2006

By Luana Karvel, Lars Kullerud, Morten Sørensen, Øystein Halvorsen, Øivind Lønne, Elaine Baker, Tina Schoolmeester, Joan Fabres, Yannick Beaudoin

The UNEP Shelf Programme (USP) is the access point for a collaboration of international organizations with expertise in marine geoscience and maritime law. It was established in response to a United Nations resolution, stating that the United Nations Environment Programme (UNEP), working through the Global Resource Information Database (GRID) system, should work in conjunction with Intergovernmental Oceanographic Commission of UNESCO (IOC) and the International Hydrographic Organization, to assist coastal States, and in particular developing States and small island developing States (SIDS) with submissions to establish the outer limits of their continental shelf under Article 76 of the United Nations Convention on the Law of the Sea (UNCLOS).

By Kokichi Iizasa

Modern Kuroko-type deposits have been much reported in submarine calderas and cauldrons in the EEZ of Japan since 1988. Some of them have been found based on heavy mineral analysis of sediments in which sulfide particles may be derived from hydrothermal sources in the ambient areas. From the end of August to early September 2007, in the middle Izu-Ogasawara arc south of Tokyo, ROV expeditions were carried out in submarine calderas in order to examine mineralogical features between intact heavy particles spouting out from sulfide chimneys and heavy minerals such as sulfides in sediments around sulfide mounds in Kuroko-type deposits, and to find more newly formed hydrothermal sulfide fields in those areas. Some preliminary results from the ROV expeditions are reported here.

Oct 15, 2007

By Robert Heydon

With the United Nations Conference on Sustainable Development fast approaching it is timely to reflect on the integral role seafloor polymetallic nodule mining will play in facilitating sustainable development and alleviating global poverty. Polymetallic nodule mining presents mankind with a unique opportunity to advance the world?s sustainable development aspirations, particularly given the ultimate beneficiaries from polymetallic nodule mining will be the billions of people around the world that require greater access to more affordable minerals for their social and economic development. This paper discusses the importance of polymetallic nodule mining in the context of sustainable development and forecasted growth trends, supply and demand dynamics, the decreasing grade and quality of terrestrial mineral resources, and the Green Economy, as well as in light of a comparative analysis that demonstrates polymetallic nodule mining offers a socially and environmentally advantageous alternative to terrestrial mining.

Jan 1, 2011

By Justin C. I. Baulch, Robina Sharpe, Steven J. Downey, John P. Feenan, Kate M. Perrin

Since becoming a public company in October 2005, Neptune Minerals has continued to advance its primary aims. Major achievements in the last year have been: • Successful completion of two simultaneous New Zealand exploration programs, Kermadec 2007 (K-07) and Colville-Monowai 2007 (CM-07); • New discovery of an inactive SMS field on the Rumble II West seamount; • Focused exploration license applications over quality areas of known SMS mineralization in arc and back-arc settings in Japan, Vanuatu, Papua New Guinea (PNG), Northern Marianas Islands (CNMI), Palau, and Italy; • Granting of licenses covering some 200,326 km2 of arc and back-arc within the EEZ of PNG and the Federated States of Micronesia (FSM); • Targeting of an additional mineralization style with extensive applications in PNG covering Conical Seamount-style Au-rich epithermal mineralization; • Welcoming Newmont Mining, one of the World’s largest mining companies, as a major shareholder; • Commissioning a scoping study to investigate options for mining and processing of SMS; Marine Minerals of the Pacific: Science, Economics and the Environment UMI2007 · The University of Tokyo, Japan Baulch 2 37th Underwater Mining Institute · 15-20 October 2007 • Invitation to contribute to, and participate in, the Meteor M73/2 Tyrrhenian Sea research program. The Company has granted exploration licenses covering 263,000 km2 in New Zealand, FSM and PNG, and a further 362,000 km2 under application in Japan, PNG, Vanuatu, Northern Mariana Islands, Palau and Italy.

By Sup Hong

Herein, concept designs of two different types of mining robots are concerned, which are aimed for developments of deep seabed mineral resources: polymetallic nodules (PMN) and seabed massive sulfides (SMS), respectively. Continuous mining concepts are presented based on technical and environmental feasibility, where the environmental and functional differences for commercial productions are investigated. Needs and roles of versatile mining robots are explained as a key of continuous mining system. The functional requirements and design characteristics of mining robots to satisfy the top requirements from customers are described comparatively. Schemes of axiomatic design and quality function deployment (QFD) are utilized: functional requirements (FR) are defined, technical requirements (TR) are figured out, design parameters (DP) are derived, and degrees of importance of design parameters are evaluated. Analogy and discrepancy in remote operation methods are put side by side. A pilot scale mining robot for PMN and a commercial scale one for SMS are suggested in form of concept designs. PMN mining robot is shaped as a multiple configuration of unit robot modules in side dimension, in which the unit robot module consists of two tracks and two pick-up modules. SMS mining robot is based on a four-tracked vehicle. Main platform is mounted on the vehicle through turn-table. Excavation device consists of two-articulated boom and cutter tool. Crushing-and-pumping units are placed same in both robot platforms.

Jan 1, 2011

By H. L. Gibson, U. Schwarz-Schampera, Mark Hannington

Ancient ore deposits provide important clues for the understanding of the origin and distribution of modern submarine hydrothermal systems. An analysis of the formation conditions, tectonic settings, and preservation of ancient seafloor mineral deposits from the recent geological past to the late Archean sheds light on the time-space relationships and diversity of mineral deposit types likely to be found in the modern oceans. Microplate tectonics that characterized ancient ore-hosting greenstone belts were strikingly similar to those active in volcanic arc environments of the western Pacific today. In such complex settings, oblique collisions, opposing subduction zones, and rapid changes in stress regimes (e.g., from compressional to tensional and back to compressional) were common, causing juxtaposition of diverse styles of mineralization. The world-class base metal deposits of the late Archean Abitibi greenstone belt of Canada, for example, were formed within a relatively short time span of ~20 m.y., in response to successive arc rifting, back-arc basin development, and exhumation of accretionary complexes along major arc-parallel crustal-scale faults. Similar processes and environments are important settings for metallogenesis in modern submarine volcanic arcs. Active marginal basins of similar size and representing similar stages of evolution are well represented in the western Pacific today and contain a similar suite of mineral deposit types. Examples from the eastern Manus Basin and adjoining New Ireland Basin (PNG) and in the Lau-Tonga-Kermadec arc-backarc system illustrate these similarities. Certain gold-rich volcanogenic massive sulfide deposits at the southern margin of the Abitibi greenstone belt (e.g., Bousquet and LaRonde deposits in the eastern Blake River Gp.) may be important ancient analogs of newly discovered gold-rich black smoker deposits found along the active fronts of today's submarine volcanic arcs.

Sep 24, 2006

By Hyun Sub Kim

Subsea mineral deposit exploration aboard the R/V Onnuri was performed along the northern Central Indian Ridge (CIR) between 8°S and 17°S in December 2009 ~ January 2010 (09IR Leg01 and 09IR Leg02) and December 2010~ January 2011 (10IR Leg01, 10IR Leg02, and 10IR Leg03). Final goal of the expedition for the first Korean research cruise on mid ocean ridge system is to define seafloor massive sulfide ore bodies through searching the active hydrothermal vents nearby spreading centers as well as to elucidate the nature of spreading segments of the northern CIR area where no systematic survey have been operated before by mapping and sampling of volcanic rocks. The preliminary result of topographical interpretations of bathymetry clearly display ocean core complex between 10°S and 11°S. The ocean core complex is featured by topographic-high area with corrugated surface. Lineaments of corrugations of the ocean core complex are clearly perpendicular to abyssal hill direction which is triggered by symmetric-normal faults. Ocean core complex are favor for hydrothermal fluid path because of the long-lived faults. In further exploration, more detailed examination, including systematic CTD casting and tows, need to narrow down actual venting site around ocean core complex. Magnetic field survey is able to estimate the location of hydrothermal vents with the properties that high temperature of hydrothermal fluids over Curie-point can cause thermal demagnetization. In magnetization intensity map, most of low magnetization zones are located at the nodal point over the ridge axis and the ocean core complex.

Jan 1, 2011

By Jung-Keuk Kang

Recently, the Korean government prepared a strategy for deep seabed mining, which consists of three stages for 20 years until 2010. The first step of the program is focused to conduct deep seabed exploration until 1993. The apparent "hurry-and-spend to catch-up" policy that the Korean government has shown in deep seabed mineral exploration was motivated by an effort to qualify a prerequisite requirement to be a pioneer investor as a developing country under the terms of Resolution II and the New York Understanding. Since 1983, KORDI (Korea Ocean Research and Development Institute) under the auspices of the Korean government has carried out deep seabed mineral exploration. The KORDI had a joint exploration program with USGS from 1989 to 1991 aiming to evaluate the potentiality of manganese nodule in the western part of Clarion-Clipperton Zone as well as that of manganese crusts in the western Pacific. In 1992, Korean government accelerates its program by the confirmation of national policy and the equipment of new built research vessel, Onnuri-Ho. The RIV Onnuri-Ho is about 1400 G/T, which is equipped with various advanced instruments including GPS, multi-beam echosounder (Seabeam 2000), multi-channel seismic system, and MDM system.

Jan 1, 1992

By Georgy A. Cherkashov

Two principal types of the hydrothermal fields in Atlantic - axial and off-axis - could be established based on their structural setting in the rift zone of the Mid-Atlantic Ridge (MAR) (Figure1). The first (axial) type is represented by five high- and three low-temperature hydrothermal sites (Table 1). All of these fields are connected with young axial effusive volcanism and related to large linear volcanic ridges or central volcanoes at the inner floor of the rift valley. The hydrothermal activity here is controlled by the intersection between longitudinal magma feeding faults and transverse weakened zones characterized by high permeability. [ ] The hydrothermal sites of the second (off-axis) type (such as Rainbow, TAG, 24°30?N, Logatchev, newly discovered 13°N (Figure 2) and possibly 16°48?N sites) are related to large tectonic dislocations forming marginal scarps of the rift valley as well as transverse discontinuities.

Jan 1, 2003

By Andrea Koschinsky, Luise Heinrich, Stefan Gößling-Reisemann

"Germany, like several other countries, has entered a contract with the International Seabed Authority (ISA) to explore the prospects of commercial manganese nodule mining in the Clarion-Clipperton Zone (CCZ). Ensuring a maximally sustainable deep-sea mining operation requires a thorough understanding of the environmental impacts associated with every step of the mining process from the extraction of the nodules at the seafloor to the refinery on land. Against this background, the project presented here applies a combination of scenario-building and life cycle assessment (LCA) to assess and evaluate the sustainability performance of the individual process steps as well as the entire mining operation.Life cycle assessment (LCA) is a comprehensive methodological framework that allows the identification and quantification of impacts occurring during a products life-cycle, as well as the analysis and evaluation of their contribution to pre-defined impact categories, such as climate change, acidification and toxicity (Rebitzer et al., 2004). Until now, LCAs with a focus on raw material extraction have almost exclusively been applied to terrestrial processes. Noteworthy exceptions are offshore drilling, offshore wind farms and ocean fishing. Hence, the first part of the project is to investigate in how far LCA can be applied to deep-sea settings and if and in what way it could be adapted to be used in a deep-sea mining context."

Jan 1, 2017